This invention relates generally to photocopying machines, and, more particularly, to the cleaning station of a photocopy machine employing liquid developer. The cleaning stations of photocopying machines employing liquid developer generally include a cleaning blade made of a resilient material, and, in many commercial machines, a cleaning roller made of a sponge material. The cleaning roller first loosens residual developer remaining on the photosensitive drum after the developed image is transferred to the copy medium, and the resilient blade scrapes or wipes the developer from the drum thereafter. If the cleaning blade and roller remain in contact with the drum surface during the time when the drum is not rotating, that is, when the copier is either on but not being used or has been turned off, for example, during a weekend, the liquid developer adhering to the blade or roller will dry out. When the copier is next started, the dried-on toner remaining on the cleaning surfaces could, in some instances adversely affect operation of the blade, the roller, and/or the photosensitive surface. The same possibility exists even if the blade and roller are lifted away from the photosensitive surface during noncopying times. In this circumstance, the dried toner could adversely affect the blade, roller and photosensitive surface when they are brought into contact with one another.
It is, therefore, an object of the present invention to provide apparatus for avoiding possible damage to the cleaning station and/or the photosensitive surface of a photocopying machine caused by the action of toner that has dried on either the photosensitive drum or the cleaning blade or cleaning roller. Another object of the invention is to avoid the possibility of damage to the cleaning station of the photosensitive drum of a photocopying machine and to provide apparatus which is simple to implement and which is reliable.
Yet another object of the invention is to avoid possible damage to the drum surface and to the cleaning roller and cleaning blade of a liquid developer photocopier and to provide apparatus which can be retrofitted to existing photocopying machines.